The use of laser sources, particularly in a laser-based image projection system, makes possible the production of images having a very large color space. However, the image quality is reduced by so-called speckles. Speckles are created when coherent light, such as laser light, hits a surface and is scattered there, which is the case, for example, when laser light impinges upon a projection screen. In this instance, at the point of observation, the light waves of all scattering centers are superposed on one another and destructive interferences occur, for one thing, in which the superposed light waves are mutually extinguished, whereby dark points are created in the point of observation, and for another thing, constructive interferences occur, in which superposing light waves are amplified, so that bright points of light are created. This leads to an overall grainy image impression, the so-called laser speckle. Since this phenomenon reduces the quality of the image, a reduction in speckles would be very desirable.
In Published International Patent Appln. No. WO 97/02507 A, an optical system is described which includes a rotating mirror which is surrounded by a conical reflector. Based on the rotation of the rotating mirror, the laser light is guided over the lateral surface of the conical reflector. Based on the rapid motion connected with this, a mixing takes place of the interference phenomena, whereby the latter can no longer be visually perceived.
The disadvantage of this device is, however, that mechanically moved components are used, so that the implementation, particularly for mobile projectors, is comparatively costly. In addition, miniaturization, which is necessary for mobile systems, is not possible.
It is therefore the object of the present invention, to provide a circuit, a laser diode receptacle, an image projector, an image projector having a laser diode, a method for adapting a circuit as well as a manufacturing method, which do not have the disadvantages of the related art and are particularly comparatively simple to implement.